6-Bit Hydraulic Manifold and Its Use in Spreading Salt

ABSTRACT

Disclosed is a system for precisely controlling distribution of saline, which employs a 6-bit manifold employing 6 solenoid valves for controlling the flow of hydraulic fluid therethrough. The manifold is in hydraulic fluid communication with motor valves. A mathematical formula or a lookup table determines the amount of saline distributed. The system is devoid of feedback. The 6-bit manifold can be employed on a salt spreader vehicle for controlling an improved flighted auger assembly for distributing granular salt from the rear of a salt spreader vehicle. The auger assembly has 3-stages of increasing diameter flights. The largest flight is at a discharge end of the auger assembly. A choke surrounds the ultimate auger flight at the auger assembly discharge end. The space between the choke and the ultimate flight is between about ⅛ and ¼ inch.

CROSS-REFERENCE TO RELATED APPLICATIONS

None.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not applicable.

BACKGROUND

The present disclosure relates to roadway snow and ice control and more particularly to a system that employs a six-bit hydraulic manifold onboard a dump truck and in a stationary brine control assembly.

A variety of commercial proposals involve spreading granular salt, brine, or brined salt on roadways for snow and ice control. Such proposals include, for example, U.S. Patents Nos. Re 33,835, U.S. Pat. Nos. 5,318,226, 5,988,535, 6,446,879, and 7,108,196. A related proposal for making brine is found in U.S. Pat. No. 6,736,153.

Despite such advances in this art, inconsistence in salt spreader output from the dump truck, auger bypass, and inaccurate reporting of salt usage still exist. Considering that in a moderately severe winter, salt usage by the State of Ohio, for example, could exceed $100,000,000 annually, there is a strong drive to improve such salt roadway distribution.

One method to decrease salt usage would be to enable salt spreader trucks to place light loads (say, 100 to 200 pounds/mile). Right now minimum accurate salt usage ranges from about 400 pounds/mile on up to 1,000 pounds/mile or more.

Of course, additional improvements in the salt spreading operation could save additional governmental funds, as well as more reliably spread salt and brined salt on roadways for ice and snow control.

It is to such improvements that the present disclosure is addressed.

BRIEF SUMMARY

Disclosed is a system for precisely controlling distribution of saline, which employs a 6-bit manifold employing 6 solenoid valves for controlling the flow of hydraulic fluid therethrough. The manifold is in hydraulic fluid communication with motor valves. A mathematical formula or a lookup table determines the amount of saline distributed. The system is devoid of feedback. The 6-bit manifold can be employed on a salt spreader vehicle for controlling an improved flighted auger assembly for distributing granular salt from the rear of a salt spreader vehicle. The auger assembly has 3-stages of increasing diameter flights. The largest flight is at a discharge end of the auger assembly. A choke surrounds the ultimate auger flight at the auger assembly discharge end. The space between the choke and the ultimate flight is between about ⅛ and ¼ inch.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and advantages of the present method and process, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:

FIG. 1 is an overhead layout of salt, brine, and brined salt generation station; and a salt truck loading/washing operation;

FIG. 2 is piping schematic for the layout in FIG. 1;

FIG. 3 is an overhead schematic for the brine making and brine storage tanks and associated piping;

FIG. 4 is an overhead schematic of the wastewater recycling tank and associated piping;

FIG. 5 is an overhead schematic of the blend tank and associated piping;

FIG. 6 is an overhead schematic of the calcium chloride (CaCl) tank and associated piping;

FIG. 7 is an overhead schematic of the BEET tank and associated piping;

FIG. 8 is schematic hydraulic diagram showing the components employed in the new 6-bit hydraulic manifold for the brine station;

FIG. 9 is block diagram illustrating the operation of the truck fill by the end user using the operator key fob;

FIG. 10 is a block diagram illustrating the operation of the recipe setup by the station manager;

FIG. 11 is the control panel used by the end user for selecting the desired truck fill;

FIG. 12 is a perspective view of a key fob;

FIG. 13 is the control panel;

FIG. 14 is the control pad on the control panel used by the station manager of FIG. 13;

FIG. 15 is left elevational view of a truck outfitted with the six-bit hydraulic manifold and other features disclosed herein;

FIG. 16 is the rear elevational view of the truck of FIG. 15;

FIG. 17 is side sectional view of the 3-stage auger with tight choke, as carried by the rear of the truck of FIG. 16;

FIG. 18 is a sectional view through line 18-18 of FIG. 17;

FIG. 19 is schematic hydraulic diagram showing the components employed in the new 6-bit hydraulic manifold for the salt spreader on the truck of FIG. 16;

FIG. 20 graphically plots steps versus gallons per minute of salt in tests of the disclosed apparatus;

FIG. 21 is the salt truck control panel;

FIG. 22 is an exemplary table of the disclosed six-bit manifold valve positions for its 63 steps; and

FIG. 23 is a block diagram of a control circuit that may be employed for the salt truck.

The drawings will be described in greater detail below.

DETAILED DESCRIPTION

As disclosed above, the ability to dispense salt in finer quantities is one way to reduce unnecessary use/consumption of salt in connection with the formation of brine and the dispensing on roadways of salt, brine, and brined salt. The six-bit manifold disclosed herein is a component that achieves such reduced salt consumption, along with additional features disclosed herein.

Referring initially to FIG. 1, an overhead layout of salt, brine, and brined salt generation station; and a salt truck loading/washing operation is depicted. A brine truck, 10, is seen in a wash bay, 12, by while a salt spreader truck, 14, loaded with granular salt is seen in its salt loading position. A control room, 16, also is seen within the building complex along with an equipment room, 18. Wash bay 12 has a power washer control panel, 20, located along one of the walls common with equipment room 18. A key fob sensor panel, 22, is located on one of the outside walls of control room 16. A recipe control panel, 24, is located on one of the inside walls of control room 16.

Housed within building area, 26, as indicated by the dashed line, is the brining complex, such as is described in U.S. Pat. No. 6,736,153. Components include a brine/vegetable matter tank, 28 (BEET), recycle tank (RECYC), 30, calcium chloride tank, 32 (CaCl), blend tank, 34 (BLEND), a first brine tank, 36 (BRINE), a second brine tank, 38 (BRINE), a brine maker, 40, a semi fill hose, 42, and truck fill hose, 44. Each of the tanks 28-38 are 10,000 gallon tanks made of and/or lined with material resistant to corrosion by salt and brine.

Referring now to the piping schematic in FIG. 2, each brine tank 36 and 38 is in fluid connection with a positive displacement pump, 46 and 48, respectively, which pumps are powered by hydraulic motors, 50 and 52, respectively. The output from the brine tank pumps 46 and 48 runs to bypass valve, 54, one branch recycling to positive displacement pumps 44 and 48 and the other branch running through a check valve, 56, and into a mixer tube, 58.

BEET tank 28 also has a positive displacement pump, 60, powered by a hydraulic motor, 62, running to a bypass valve, 64, having a recirculation line indicated by the dotted line and also running through a check valve, 66, into mixer tube 58. In similar fashion, CaCl tank 32 also has a positive displacement pump, 68, powered by a hydraulic motor, 70, running to a bypass valve, 72, having a recirculation line indicated by the dotted line and also running through a check valve, 74, into mixer tube 58.

The flow exiting mixer tube 58 runs through a valve, 76, which has a flow back through a check valve, 78, into blend tank 34 and a flow running through a check valve, 80, to another tee, 82, and into truck fill hose 44. The material in blend tank 34 flows through a check valve, 84, into tee 82 and onward to truck fill hose 44.

Material in brine tank 38 can be pumped by a pump, 86, through a check valve, 88, and into a tee, 90, to truck fill hose 44. Alternatively, material in brine tank 38 can be pumped by a high volume pump, 92, and into semi fill hose 42.

Referring now to FIG. 3, brine tanks 36 and 38 are seen. As mentioned earlier, each tank has a maximum capacity of 10,000 gallons. Brine tank 36 is connected to brine tank 38 through a line 47. A sensor, such as a float sensor, 94, indicates that brine tank 38 is filled to capacity, which causes any brine flow into brine tank 36 and 38 to cease. Brine tank 36/38 can be filled from brine maker 40, which receives material from RECYC tank 30 and/or domestic water, which flows using a centrifugal pump, 95, and into brine maker 40. A recirculation loop, 96, uses another centrifugal pump, 98. A centrifugal pump, 100, pumps brine from brine maker 40 into brine tanks 36 and 38.

Referring now to FIG. 4, RECYC tank 30 is fitted with a float sensor, 102, indicates that RECYC tank 30 is filled to capacity, which causes any flow into RECYC tank 30 to cease. Material used in wash bay 12 is collected and recycled into RECYC tank 30, through a heater, 104, which keeps RECYC tank from freezing.

Referring now to FIG. 5, a sensor, such as a float sensor, 106, indicates that BLEND tank 34 is filled to capacity, which causes any flow into BLEND tank 34 to cease. Material from mixing tube 58 can flow into a recirculation loop, 108, powered by a pump, 110, for causing a circulation flow inside BLEND tank 34 with provision to divert the recirculation loop flow to fill hose 44.

Referring to FIG. 6, CaCl tank 32 is shown with provision of its contents, 30% aqueous calcium chloride, to calcium chloride pump, 68, in FIG. 2. Again, the capacity of CaCl tank 32 is 10,000 gallons.

Referring to FIG. 7, BEET tank 28 is shown with a recirculation loop, 112, for causing a recirculation flow thereinside using another centrifugal pump, 114. While this tank often will be filled with byproduct from sugar beet production, other vegetable material may be used alone and/or in addition to the indicated sugar beet byproduct. Such vegetable material further depresses the freezing point of brine.

Referring now to FIG. 8 whereat a schematic hydraulic diagram showing the components employed in the new 6-bit hydraulic manifold for the brine station is set forth. Important in using such 6-bit hydraulic manifold is that no feedback loop is required. Simply, such 6-bit hydraulic manifold provides 63 steps in controlling flow, which yields an error of about 2% at most and often less than about 1%. In particular, such manifold relies simply on 6 precise orifices that can be used in any combination, yielding the noted 63 steps. Only one of the three 6-bit manifolds will be described in detail, as the other two shows 6-bit hydraulic manifolds operate in precisely the same fashion. General operation of a similar 4-bit device is disclosed in U.S. Pat. No. 7,108,196 (FIG. 6). The present 6-bit manifold operates in similar fashion.

Referring now to a 6-bit hydraulic manifold, 116, six-solenoid controlled orifices of different size are shown. In particular, a solenoid, 118, uses a suitably sized orifice for a 0.25 gpm (gallon per minute) flow; a solenoid, 120, uses a suitably sized orifice for a 0.5 gpm (gallon per minute) flow; a solenoid, 122, uses a suitably sized orifice for a 1.0 gpm (gallon per minute) flow; a solenoid, 124, uses a suitably sized orifice for a 2.0 gpm (gallon per minute) flow; a solenoid, 126, uses a suitably sized orifice for a 4.0 gpm (gallon per minute) flow; and a solenoid, 128, uses a suitably sized orifice for a 8.0 gpm (gallon per minute) flow. Manifolds 130 and 132 are identical to manifold 116. Manifold 116 controls the BEET tank; manifold 130 controls the CaCl tank; and manifold 132 controls the Brine tank 38.

Associated with manifold 116 is a compensator, 134, functioning to provide a constant speed or pressure drop for motor 62 BEET tank 28. Compensators 136 and 138 generally provide the same function as compensator 134 for CaCl tank motor 70 and the brine tank motors 50 and 52, respectively. Operator input for the mixing of concentration in BEET tank 28 is at pump 60; pump 58 for CaCl tank 32, and pumps 46/48 controlled by valve 140 and manifold 132 for brine tanks 36, 38. Operator input for motor 85 of pump 86 is through valve 142 (truck fill brine only) and motor 91 of pump 92 through valve 44 (semi fill), and motor 109 of pump 110 through valve 146 (stir blend tank or truck fill from blend tank) and motor 113 of pump 114 through valve 148 (stir BEET tank).

Referring now to FIGS. 9-12, displayed is the block diagram illustrating the operation of the truck fill by the end user using an operator key fob, 158 (see FIG. 12), and key fob sensor panel 22 (see FIG. 1). Operation commences at START at block 160 with the truck operator scanning key fob 158 at block 162 by passing key fob 158 over sensor area, 168 of panel 22 (see FIG. 11). At block 164, the operator rotates a knob, 170 on panel 22 (see FIG. 11), to select filling a semi, filling a truck with brine, or filling a truck with a mixed recipe. If the operator selects “Semi”, the operation proceeds to block 172 where the operator pulls a button, 174 on panel 22 (FIG. 11). Operation then proceeds to block 176 where the computer selects semi fill pump. Operation next proceeds to block 178 where the pump 92 is activated to begin delivery of product into the semi. At block 180, the operator pushes button 174 to stop pump delivery of product. Operation then ends at block 182.

When the operator rotates knob 170 to select “mix”, operation proceeds to block 184 where the operator pulls knob 174 “on”. Operation proceeds to box 186 where the computer selects the current mix recipe. Operation then proceeds to box 188 where the pumps 46, 48, 60, and 68 are activated to begin delivery of product. At box 190, the operator pushes knob 174 in to stop delivery of product. Operation then ends at box 192.

When the operator rotates knob 170 to select “brine”, operation proceeds to block 194 where the operator pulls knob 174 “on”. Operation proceeds to box 196 where the computer selects brine only pump 86. Operation then proceeds to box 198 where pump 86 is activated to begin delivery of product. At box 200, the operator pushes knob 174 in to stop delivery of product. Operation then ends at box 202. Referring now to FIGS. 10-14, control panel 24 is shown in FIG. 13 containing an interactive display, 204, shown enlarged in FIG. 14. The block diagram in FIG. 10 starts at box 206 with the plant operator at box 208 selecting values for flow rate for brine, CaCl, BEET or other agricultural agent, each by percentage. Such selection is made on control panel 204 as indicated by the numerical values of percent displayed thereon. The computer automatically calculates the flow rates for each tank based on the percentages inputted with an indicated delivery rate. Operation proceeds to block 210 where the operator saves the recipe by assigning a one or two character value using the lower number inputs on control panel 204. At block 212, the operator can recall any saved recipe by entering the correct assigned number. Operation ends at block 214.

The computer retains a formula in memory for calculating/determining the combination of each aperture to be open/closed by their respective solenoid valves. As an example of such calculations for Brine and CaCl, the following is given:

AG_GPM=0.356*AG_SET

CALC_GPM=0.356*CALC_SET

BRINE_GPM=0.712*BRINE_SET

TOTAL_GPM=AG_GPM+CALC_GPM+BRINE_GPM

AG_%−(AG_GPM/TOTALGPM)*100

CALC_%=(CALC_GPM/TOTALGPM)*100

BRINE_%=(BRINE_GPM/TOTALGPM)*100

Referring now to FIGS. 15 and 16, delivery truck 14 is illustrated. For a detailed description of it, reference is made to the description of truck 10 in U.S. Pat. No. 6,382,535. The '535 truck will be the same as the present truck, except for the use of the 6-bit manifold and modified auger disclosed herein.

Referring now to FIGS. 17 and 18, an auger assembly, 216, includes a housing, 218, and auger 220 having 3-stages, 220 a, 220 b, and 220 c, each with increasing flight diameter, respectively. A motor, 221, drives auger 220. At the discharge end of the auger, a housing, 228, houses auger 220. A close fitting choke, 230, fits around the end flight on auger 220 to ensure a reliable and consistent delivery of salt. A gap of around ⅛ to ¼ inch between the choke and auger flight is desired. The increasing diameter flights help resist cavitation and ensure the ability to delivery salt at the low rates discussed above. Additionally, an eccentric vibrator, 231 (FIG. 15) was added to the bed of truck 14 to assist in urging salt to be moved from the bed to the auger when the salt was near exhaustion. A sensor activates the vibrator when the rate of salt feed to the auger diminishes through pressure switches 236 and 238 in FIG. 19.

Referring to FIG. 19 where the 6-bit manifold for truck 14 is set forth, it is substantially similar to the 6-bit manifold described in FIG. 8 for the brine plant. In the present truck 6-bit manifold, the apertures are designed for ¼, %, 1, 2, 4, and 8 GPM (gallons per minute). Sixty-three steps, thus, are possible from such manifold design for enabling delivery from as little as 100 pounds/mile on up to 1,000 pounds/mile or greater with intermediate values of 200, 300, 400, 500 pounds/mile, etc., fully implementable.

Unlike the plant 6-bit manifold, the truck 6-bit manifold uses a lookup table, an example of which is given in FIG. 22. Manifold 232 controls the auger/spreader and utilizes solenoid valves 234 a (0.25 gpm), 234 b (0.5 gpm), 234 c (1.0 gpm), 234 d (2.0 gpm), 234 e (4.0m gpm), and 234 f (8.0 gpm). A temperature sensor is seen at 242. The main relief is seen at 244. Item 245 is the auger compensator input. Manifold 246 controls the spinner and manifold 247 controls the wetting, as is described in U.S. Pat. No. 7,108,196, so a detailed description of these will not be given herein. The same is true for bed/plow sections 248 and 249.

FIG. 20 graphically plots steps versus gallons per minute of brine in tests of the disclosed apparatus in FIG. 19. The truck operator control panel is illustrated in FIG. 21. Its operation is as described in U.S. Pat. No. 7,108,196.

Referring to FIG. 23, a block diagrammatic representation of a microprocessor driven control function for vehicle 14 and it associated snow-ice control features is identified generally at 250. The control function operates in conjunction with six sensor functions. In this regard, a hydraulic system low fluid sensor is provided as represented at block 252. A hydraulic system temperature sensor function is provided as represented at block 253. Hydraulic system low-pressure sensor function is provided as represented at block 254, and a hydraulic system high-pressure sensor is provided as represented at block 255. The functions represented at blocks 252-255 provide inputs as represented at respective lines 258-261 to the analog-to-digital function represented at sub-block 264 of a microprocessor represented at block 266. Microprocessor 266 may be provided as a type 68HC11 marketed by Motorola Corporation. Device 266 is a high-density complimentary metal oxide semi-conductor with an eight-bit MCU with on-chip peripheral capabilities. These peripheral functions include an eight-channel analog-to-digital (NO) converter as noted above. An asynchronous serial communication interface is provided and a separate synchronous serial peripheral interface is included. Its main sixteen-bit, free-running timer system has three input capture lines, five-compare lines, and a real time interrupt function. An eight-bit pulse accumulator sub-system can count external events or measure external periods. Device 266 performs in conjunction with memory (EPROM) as represented at bi-directional bus 270 and block 272. Communication also is provided via bus 270 with random access memory (RAM) as represented at 274 and function 274 may be provided, for example, as an OS 1644 non-volatile time-keeping RAM marketed by Dallas Semi-Conductor Corporation. The LCD display is represented at block 276. A type DV-16100 S1FBLY assembly, which consists of an LCD display, a CMOS driver and a CMOS LSI controller marketed by Display International of Oviedo, Fla., may provide this function. Digital sensor inputs to the microprocessor function 266 are provided from a speed sensor represented at block 278 and line 280. In general, the speed sensor will output 40,000 pulses per mile of vehicle travel, which equates to 7.5 pulses per foot. A two-speed sensor digital input is supplied to microprocessor 266 as represented at block 282 and line 284.

The circuit power supply is represented at block 286. This power supply, providing two levels of power, distributes such levels where required as represented at arrow 288. Supply 286 is activated from the switch inputs of truck control panel (FIG. 21) and represented in the instant figure at block 290 and arrow 292. These various console and auxiliary console or control box switch inputs as represented at block 290 also are directed, as represented at arrow 294 to serial parallel loading shift registers as represented at block 296. As represented by bus 298, communication with the function at block 296 is provided with the microprocessor function represented at block 266. Bus 298 also is seen directed to a 48-channel driver function represented at block 300. Function 300 may be implemented with a 48-channel serial-to-parallel converter with high voltage push-pull outputs marketed as a type HV9308 by Supertex, Inc. The output of the driver function represented at block 300 is directed, as represented by arrow 302, to an array of metal-oxide semiconductor field effect transistors (MOSFETS) as represented at block 304. These devices may be provided as auto-protected MOSFETS type VNP10N07F1 marketed by SGS-Thomson Microelectronics, Inc. The outputs from the MOSFET array represented at block 304 are directed as represented by arrow 306 to solenoid actuators as represented at block 308. An RS232 port is provided within the control function 250 as represented at block 310 and arrow 312 communicating with microprocessor function 266.

While the device and method have been described with reference to various embodiments, those skilled in the art will understand that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope and essence of the disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from the essential scope thereof. Therefore, it is intended that the disclosure not be limited to the particular embodiments disclosed, but that the disclosure will include all embodiments falling within the scope of the appended claims. In this application all units are in the metric system and all amounts and percentages are by weight, unless otherwise expressly indicated. Also, all citations referred herein are expressly incorporated herein by reference. 

I claim:
 1. A system for precisely controlling distribution of saline, which comprises: a 6-bit manifold comprising 6 solenoid valves for controlling the flow of hydraulic fluid therethrough, said manifold in hydraulic fluid communication with motor valves for controlling the distribution of saline in the form of one or more of granular salt or brine, the amount of saline distributed being determined by a mathematical formula or a lookup table, said system devoid of feedback.
 2. The system of claim 1, wherein said 6-bit manifold has apertures sized for controlling ¼, ½, 1, 2, 4, and 8 GPM of saline delivery.
 3. The system of claim 1, wherein said 6-bit manifold controls between about 100 and 1000 pounds/mile of saline delivery.
 4. The system of claim 1, wherein said 6-bit manifold uses a lookup table or formula for determining the delivery of saline.
 5. The system of claim 1 mounted in a saline delivery vehicle.
 6. The system of claim 5 in combination with an improved flighted auger for distributing granular salt from the rear of a salt spreader truck, which comprises: (a) said auger having 3-stages of increasing diameter flights, the largest flight being at a discharge end of said auger; and (b) a choke surrounding said ultimate auger flight at the auger discharge end, space between said choke and said ultimate flight being between about ⅛ and ¼ inch.
 7. Method for precisely controlling distribution of saline from a vehicle, which comprises: controlling from said vehicle the distribution of saline in the form of one or more of granular salt or brine with a 6-bit manifold comprising 6 solenoid valves for controlling the flow of hydraulic fluid therethrough, said manifold in hydraulic fluid communication with motor valves for controlling the distribution of saline in the form of one or more of granular salt or brine, the amount of saline distributed being determined by a mathematical formula or a lookup table, said system devoid of feedback.
 8. The method of claim 7, wherein said delivery of saline is controlled by said 6-bit manifold having apertures sized for controlling ¼, ½, 1, 2, 4, and 8 GPM of saline delivery.
 9. The method of claim 7, wherein said delivery of saline controlled by said 6-bit manifold ranges between about 100 and 1000 pounds/mile of saline delivery.
 10. The method of claim 7, wherein a lookup table or formula is used by said 6-bit manifold for determining the delivery of saline.
 11. An improved flighted auger assembly for distributing granular salt from the rear of a salt spreader vehicle, which comprises: (a) said auger assembly having 3-stages of increasing diameter flights, the largest flight being at a discharge end of said auger; and (b) a choke surrounding said ultimate auger flight at the auger assembly discharge end, space between said choke and said ultimate flight being between about ⅛ and ¼ inch.
 12. The improved flighted auger assembly of claim 11, wherein said salt spreader vehicle has a bed for storage of granular salt and said bed is fitted with a vibrator for urging granular salt into said auger assembly. 